Study of Natural Radionuclides of some igneous rocks inarabian Shield (South of Al- Madinah Al- Munawarah), Saudi Arabia. Safia H. Q.

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1 Study of Natural Radionuclides of some igneous rocks inarabian Shield (South of Al- Madinah Al- Munawarah), Saudi Arabia Safia H. Q. Hamidalddin * King Abdulaziz University, Faculty of Science, Jeddah, Saudi Arabia safiahqh@yahoo.com Abstract: Igneous rocks are geologically important for their minerals and global chemistry information and for their economic content such as basalt, Andesite, and Diorite.etc. Western Saudi Arabia (the Arabian Shield) is covered with fields of lava known asharrats. Al-Madinah is situated in a depositional basin surrounded by lava plateaus and hills and is bounded by Harrats which consists of igneous rocks.six samples were collected from south of Al- Madinah and confined by the following co-ordinate Latitude N: to N: and Longitude E: to E: The dried samples were analyzed by XRD for the mineral constituents and the major concentrations for the samples are Augite, Albite, Biotite, Clinochlore, Pargasite, and Quartz.Also, the samples were analyzed by atomic absorption spectroscopy for the Al, Ca, K, Bi,Pb, and Th, concentrations in ppm and/or percent, values ranged from 7.13% to 8.79%, 1.21% to 6.92%, 0.54% to 4.24%, <10 ppm, ppm to 77.06ppm, and <1 ppm to 5.58 ppm respectively.gamma spectroscopy was applied to determine the concentrations of the radionuclides in the samples. There is disequilibrium between 238 U and 226 Ra, was used to find the concentrations Bq/.kg dry weight of the 238 U which ranged from to with mean value While there is equilibrium between daughters ( and ) of 226 R, so their activities concentrations Bq/.kg dry weight were calculated for 226 Raactivities concentrations Bq/.kg dry weight. The activity concentrations Bq/.kg dry weight ranged from to , with mean value Samples show high uranium than radium, and these represent the disequilibrium in the 238 U-series. The activity concentrations of 232 Th were calculated from its short half life daughters 228 Ac and 208 Tl since there is secular radioactivity equilibrium in 232 Th series. The activity concentrations Bq/.kg dry weight of the 232 Th ranged from to with mean value The activity concentrations Bq/.kg dry weight of the 235 U were for sample 1ba and for sample 2an and ND for the rest of samples. For 40 K, the activity concentrations Bq/.kg dry weight of ranged from to with mean value The average Ra eq valuewas Bq/kg which is higher than the internationally accepted value 370 Bq/kg and Annual Effective Dose (msvy/h) ranged from 0.08 to 0.59 with mean value The results can be considered as base values for distribution ofnatural radionuclides in the region and reference information. [Safia H. Q. Hamidalddin. Study of Natural Radionuclides of some igneous rocks inarabian Shield(South of Al- Madinah Al-Munawarah), Saudi Arabia. J Am Sci 2012;8(12): ]. (ISSN: ) Keywords: Igneous rocks-harrats- atomic absorption spectroscopy- The average Ra eq. 1. Introduction The rocks of the Arabian shield are mostly Neoproterozoic in age, but some date from the Archean and Paleoproterozoic, and a few intrusions yield Cambrian ages. Some areas in the east-central shield in Saudi Arabia contain Paleoproterozoic igneous rock, parts of a microplate indicated by an inherited continental isotopic signature that was largely destroyed by later intrusions (Saudi Geological Survey, 2012).The shield rocks result from the developmentand accretion of multiple volcanic arcs, separate sedimentary basins, and many different magmatic events, it is necessary to establish local stratigraphy to adequately account for these rocks and their relationships (Johnson and Kattan F. H, 2001). The study of igneous rocks is important as products of deep earth processes such as melting of solid rock and crystallization of molten rock (magma), they provide researchers with important information regarding the mineralogical and chemical composition of the earth's interior. Also, some igneous rocks such as Granite and basalt have commercial and industrial use because of its high clay mineral content. In the manufacture of brick,granite is used for countertops and building facings. Basalt has been used in construction of buildings, pavers, and countertops as well.so, the radioactivity contents of various radionuclides in rocks may play an important role in health physics and geo- scientific research. These radionuclides pose exposure risks externally due to their gamma-ray 1524

2 emissions and internally due to radon and its progenies, which emit alpha particles. There are many studies about the concentrations of naturally-occurring radionuclides in igneous rocks from different regions of the world, these studies show that high levels of radiation are associated with igneous rock such as granite and basalt [Ahmed et al, 2006, El-Arabi, 2007]. Harb et al, 2008,,,Awodugba et al, 2011, Raslan and El- Feky, 2012]. Western Saudi Arabia is covered not only with sand, but also with vast fields of lava which are known as harraat. Harraat in Saudi Arabia together form one of earth s largest alkali basalt regions, covering 180,000 square kilometers (Saudi Geological Survey, 2012). Al-Madinah is situated in a depositional basin surrounded by lava plateaus and hills within the western part of the Arabian Shield. Its ground surface elevations are around m above sea level (Matsah and Hossain, 1993). Al- Madinah area is bounded by Harrats which consists of igneous rocks. Igneous rocks are geologically important for their minerals and chemistry information. Also, the radioactivity contents of radionuclides in rocks play an important role in health physics researchers (igneous granite and igneous basalt are used as building stones). In this work, the main aim is to study some igneous rockssamples collected from differentlocations at South of Al- Madina Al- Monwarehby X-RD spectroscopy to assign the mineral and chemical composition for each sample, atomic absorption spectroscopy was applied for some mineral concentrations in ppm and / or percent, and gamma spectroscopy to determine the concentrations of the radionuclides in the samples. 2. Experimental techniques 2.1. Sample preparation Six samples were collected from south of Al- Madinah and confined by the following coordinatelatitude N: to N: and Longitude E: to E: as shown in figure 1. They contain the following: Basalt samples (1ba and 6ba) which is the most widespread of all igneous rocks, and comprises more than 90% of all volcanic rocks, it is used as aggregate, fill etc. in the construction and road industries, armour rock for seawalls, dimension stone, e.g. stone walls, curb stones, paving stones etc. Andesitesamples (2an and 4an) is an extrusive rock intermediate in composition between rhyolite and basalt,it can be used as aggregate, fill etc. in the construction and road industries (often not ideal for concrete aggregate because of high silica content). Diorite sample (3di)is an intrusive rock intermediate in composition between gabbro and granite. It is produced in volcanic arcs, and in mountain building where it can occur in large volumes as batholiths in the roots of mountains,it can be used as aggregate, fill etc. in the construction and road industries (often not ideal for concrete aggregate because of high silica content) and cut and polished for dimension stone for building facings, foyers etc.microgranodiorite sample (5mi)is an intrusive rock, intermediate in composition between diorite and granite. Although often similar in appearance to diorite or granite, it has highquartz content. It is commonly produced in volcanic arcs, and in mountain building where it emplaces as large batholiths in mountain roots. Microgranodiorite is can be used as aggregate, fill etc. in the construction and road industries (often not ideal for concrete aggregate because of high silica content) and cut and polished for dimension stone for building facings, foyers etc.(saudi Geological Survey,2012). Fig. 1 Map of the samples locations Samples were grounded, sieved by 1mm x 1mm, then dried to 95 C for 24 hours in order not to lose the volatile polonium or cesium. The dried fine grained samples were packed in polyethylene Marinelli beakers for gamma spectroscopy, and then stored for up to four months to reach secular equilibrium between 238 U and 232 Th and their progenies. Measurements Ten grams of the dried samples were analyzed by XRD model Burker XR-D D8 Advance for the mineral constituents, also 10 gramsof the dried samples were analyzed by atomic absorption model A Analyst 700 for the Al, Ca, K, Bi,,PbTh, concentrations in ppm and/or percent. Samples were analyzed for concentrations of 238 U, 232 Th series, 235 U, and 40 K using the gamma spectrometer based on 1525

3 Canberra hyper pure germanium detector "HPGe" coaxial detector with relative efficiency of 20% and FWHM 4.2 kev at 1461 kev, the measurements were done for a time period of twenty four hours. For 238 U, a gamma-ray line of energy 63.29keV, of 234 Th, was used to find the concentrations. Gamma-ray lines of energies , , , , and kev resulting from the decay of daughters 214 Pb and 214 Bi radionuclides (which they are in secular radioactivity equilibrium) were used to determine the activity concentrations of 226 Ra. The gamma-ray lines at338.42, , , , and kev from the decay of short half life daughters 228 Ac and 208 Tl were used to determine the activity concentrations of 232 Th respectively (since there is secular radioactivity equilibrium in 232 Th series); while the143.8and transitions were used to determine the activity concentrations of 235 U and 40 Krespectively. After analyzing the spectrum, the net counting rates for each detected photo peak were used to calculate the specific activity (A) in Bq/Kg for each detected nuclide using the following equation:(amrani & Tahtat M., 2001). A = (1) Where: c is the net counting rate of a specific gamma ray (count per second) M is the mass of the samples (kg) is the transition probability of gamma-decay is the detector efficiency at the specific gamma-ray energy. Distribution of 226 Ra, 232 Th and 40 K in environment is not uniform, so that the radioactivity has been defined in terms of radium equivalent activity (Ra eq ) in Bq/kg to compare the specific activity of materials containing different amounts of 226 Ra, 232 Th and 40 K. Equation (2) was used to determine Ra eq (Bq/.kg) (Tufail et al., 2006): Ra eq (Bq/.kg) =C Ra +(C Th x 1.43) + (C K x0.077) (2) Where: C Ra, C Th and C K are the concentrations Bq/kg for radium, thorium and potassium respectively. Besides the radium equivalent activity, the total air absorbed dose rate D(nGy/ h) in the outdoor air at 1 m above the ground due to the activity concentrations of 226 Ra, 232 Th and 40 K (Bq/ kg) dry weight was calculated using the equation (3) (UNSCEAR 2000; Veigaet al., 2006) D(nGy/h) = 0.462C Ra C Th C K (3) Where:C Ra, C Th, and C K are the specific activities (concentrations) of 226 Ra, 232 Th and 40 K in Bq /kg respectively. By using a conversion factor of 0.7 SvG/y and outdoor occupancy factor of 0.2 (people spend about 20% of their life outdoor) the Annual Effective Dose (in msv/y) received by population can be calculated using equation: D eff (msv/y) = D(nGy/h) 8,766 h 0.7(SvG/y ) (4) Where:D(nGy/h) is the total air absorbed dose rate in the outdoor. 8,766 h is the number of hours in 1 year is conversion factor of nano and milli. 3. Results and Discussions 3.1 Results of XRD spectrometer and Atomic Absorption spectrometer: From the obtained results of XRD spectrometer and Atomic Absorption spectrometer represented in tables (1&2), it can be seen that, sample 1ba major constituent is AUGITE, it has the lowest concentration values inal (7.13%) of all samples, while the concentrations of Ca (6,92%) and for Th (5.58 ppm=22.88 Bqlkg) are the highest values of all samples. The concentrations ranged from4.08%, <10 ppm, and 19.77ppm for K, Bi, and Pb respectively. Sample 2an major constituents are ALBITE and BIOTITE. Concentrations of Al, Ca,, K, Bi, Pb and Th ranged from 7.38, 4.11, 2.22 in %, and <10, 17.54, and <1 in ppm respectively. Sample 3di major constituents are ALBITE, CLINOCHLORE, PARGASITE, QUARTZ. This sample has the highest values of concentrations in Al (8.79%) and Pb (77.06) ppm of all samples, concentrations of Ca,, K, Bi, and Th ranged from4.26 and 2.12 in % and <10 and <1 in ppm respectively. Sample 4an major constituents are ALBITE, CLINOCHLORE, and, PARGASITE. The Concentrations of K(0.54%) and Pb (11.54 ppm) are the lowest values of all samples. The Concentrations of Al, Ca, Bi, and Th ranged from8.67, 4.83 in %, <10, <1ppm respectively. Sample 5mi major constituents are ALBITE, CLINOCHLORE, and, PARGASITE. The Concentrations of Al, Ca, K, Bi, Pb and Th ranged from 8.39, 5.45, 1.33 in% and<10, 38.17, and <1 in ppm respectively. Sample 6ba major constituents are ALBITE, QUARTZ. This sample has the highest values of concentrations in K (4.24%) of all samples. The Concentrations of Al, Ca, Bi, Pb, and Th ranged from7.26, 1.21 in % and <10, 44.32inppm, and (4.06 ppm-16.65bq/kg) respectively, with additional minor and trace concentrations. 1526

4 Table (1): The mineral constituents of six samples of igneousrocks analyzed by XRD spectrometer, (Leetet al., 1982, and Mineral Data, 2012). Sam. code 1ba 2an 3di 4an 5mi 6ba Major Minor Trace AUGITE(Ca,Na)(Mg,Fe,Al, Ti)(Si,Al) 2O 6 BIOTITE(K(MgFe 2+ ) 3AlSi 3 O 10(OH F) 2), CLINOCHLORE(MgFe 2+ ) 5S i 3Al 2O 10(OH) 8, PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH ) 2, QUARTZ( SiO 2) CLINOCHLORE(MgFe 2+ ) 5S i 3Al 2O 10(OH) 8, PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH ) 2, CLINOCHLORE(MgFe 2+ ) 5S i 3Al 2O 10(OH) 8, PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH ) 2, QUARTZ( SiO 2) BIOTITE (K(MgFe 2+ ) 3AlSi 3O 10(OH F) 2), JUSITE(CaNaK) 5(SiAl) 6O 15H 2O, MAGNETITE(Fe 3+ 2Fe 2+ O 4), PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH) 2,QUA RTZ(SiO 2) AUGITE(Ca,Na)(Mg,Fe,Al,Ti)(Si, Al) 2O 6MAGNETITE(Fe 3+ 2Fe 2+ O 4), MICROCLINE(KAlSi 3O 8),QARTZ ( SiO 2) BIOTITE(K(MgFe 2+ ) 3AlSi 3O 10(OH F) 2), MICROCLINE(KAlSi 3O 8), AUGITE(Ca,Na)(Mg,Fe,Al,Ti)(Si, Al) 2O 6MICROCLINE (KAlSi 3O 8), QUARTZ( SiO 2), BIOTITE(K(MgFe 2+ ) 3AlSi 3O 10(OH F) 2), QUARTZ( SiO 2) CLINOCHLORE(MgFe 2+ ) 5Si 3Al 2O 1 0(OH) 8, MICROLINE(KAlSi 3O 8) ANKERITECaFe Mg 0.3Mn (CO 3) 2,CLINOCHL ORE(MgFe 2+ ) 5Si 3Al 2O 10(OH) 8, DOLOMITE(CaMg(CO 3) 2), NONTRONITENa 3Fe 3+ 2Si 3AlO 10(OH) 24(H 2O), OFFRETITEK 2,Ca,Mg) 2.5A l5si 13O 36 15(H2O), PARTHEITECa 2Al 4Si 4O 15(OH) 2 4(H 2O) CLINOCHLORE(MgFe 2+ ) 5Si 3Al 2O 10(OH) 8, DOLOMITE(CaMg(CO 3) 2), HOHMANNITEFe 3+ 2(SO 4) 2(OH) 2 7(H 2O), MONTMORILLONITE Na 2Ca 1Al 2Si 4O 10(OH) 2(H 2O) 10, PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH) 2, RAMSBECKITECu,Zn) 15(SO 4) 4(OH) 22 6(H 2O) AUGITE(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al) 2O 6CALCITE( CaCO 3), HALITE(NaCl), MAGNETITE(Fe 3+ 2Fe 2+ O 4), MONTMORILLONITE Na 2Ca 1Al 2Si 4O 10(OH) 2(H 2O) 10, NONTRONITE Na 3Fe 3+ 2Si 3AlO 10(OH) 24(H 2O), BIOTITE(K(MgFe 2+ ) 3AlSi 3O 10(OH F) 2),CALCITE(CaCO 3), HALITE(NaCl),MAGNETITE(Fe 3+ 2Fe 2+ O 4), PROBERTITENaCaB 5O 7(OH) 4 3(H 2O),SLAVIKITE NaMg 2Fe 3+ 5(SO 4) 7(OH) 6 33(H 2O) ALLOPHANE (Al 2O 3)(SiO 2) (H 2O),AUGITE(Ca,Na)(Mg,Fe,A l,ti)(si,al) 2O 6CALCITE(CaCO 3),MAGNETITE(Fe 3+ 2Fe 2+ O 4) NONTRONITENa 3Fe 3+ 2Si 3AlO 10(OH) 24(H 2O), SAPONITE (CaNa)3(Mg,Fe ++ ) 3(Si,Al) 4O 10(OH) 24(H 2O), BIOTITE (K(MgFe 2+ ) 3AlSi 3O 10(OH F) 2), CALCITE(CaCO 3),GMELINITE(Na 2Ca)Al 2Si 4O 12 6( H 2O), GYPSUMCa(SO 4) 2(H 2O),MAGNETITE(Fe 3+ 2Fe 2+ O 4) MONTMORILLONITE Na 2Ca 1Al 2Si 4O 10(OH) 2(H 2O) 10,PARGASITE NaCa 2Mg 3Fe 2+ Si 6Al 3O 22(OH) 2, Table(2): Concentrations of Al, Ca, K, Bi, Pb and Th,for igneous rocks samplesmeasured by Atomic Absorption Analyzer. Elements Al Ca K Bi Pb Th Samp. D L code Units % % % ppm ppm ppm Bq/kg 1ba < an < <1 <4.10 3di < <1 <4.10 4an < <1 <4.10 5mi < <1 <4.10 6ba < Concentrations of 238 U 226 Ra series: Rocks samples were measured using the gamma spectrometer. The results in table (3) show that,there is disequilibrium between 238 U and 226 Ra, a 63.29KeV photopeak, which comes the decay of was used to find the concentrations. The activity concentrations Bq/.kg dry weight of the 238 U ranged from to with mean value While there is equilibrium between the daughters and of 226 Ra,the activities of and were used to calculate the concentrations for 226 Ra. Theactivity concentrations Bq/.kg dry weight ranged from to , with mean value Samples show high uranium than radium, and these represent the disequilibrium in the 238 U-series. 1527

5 3.3. Concentrationsof 232 Th: The decay of short half life daughters 228 Ac and 208 Tl were used to determine the activity concentrations of 232 Th since there is secular radioactivity equilibrium in 232 Th series. The activity concentrations Bq/.kg dry weight of the 232 Th ranged from to with mean value Comparing the concentrations values Bq/.kg dry weight of 232 Th for samples 1ba and 6ba measured by Atomic Absorption Analyzer (22.88 and 16.65) with the concentrations values Bq/.kg dry weight of 232 Th measured by the gamma spectrometer ( and ,which were calculated from the decay of short half life daughters 228 Ac and 208 Tl). It turned out to be not consistent which showed that there is disequilibrium between 232 Th and its series Concentrationsof 235 U The activity concentrations Bq/.kg dry weight of the 235 U were for sample 1ba and for sample 2an and ND for the rest of the samples Concentrationsof 40 K The activity concentrations Bq/.kg dry weight of the 40 K ranged from to with mean value Table (3): The activities concentrations Bq/.kg dry weight of the 238 U, 226 Ra, 232 Th, 235 U and 40 K for igneous rocks samples. Samp. code Lat. and Long. 238 U 226 Ra 232 Th 235 U 40 K 1ba N: E: an N: E: di N: E: ND an N: E: ND mi N: E: ND ,31 6ba N: E: ND Min Max Mean TheRa Eq (Bq/kg), D(nGy/h), and D eff (msv/y The radium equivalent activities of samples under investigation were calculated and were shown in table 4. The average Raeq value for the studied area was Bq/kg which is higher than the internationally accepted value 370 Bq/kg(UNSCEAR, 2000). The highest value of Ra Eq is in sample 1ba and the lowest one is in 4an. Annual Effective Dose (msvy/h) ranged from 0.08 to 0.59 with mean value These calculated values were lower than the estimated world averaged values ( 1for D eff (msv/y). Table (4): TheRa Eq (Bq/kg), D(nGy/h), and D eff (msv/y) for igneous rocks samples. Samp. No. (Ra Eq Bq/kg) D(nGy/h) D eff (msv/y) 1ba an di an mi ba Min Max Mean

6 4. Conclusion The obtained results of XRD spectrometer show that the major concentrations for the samples are AUGITE, ALBITE, BIOTITE, CLINOCHLORE, PARGASITE, and QUARTZ. The concentrations values of Al, Ca, K in %, Bi, Pb, and Th in ppm, for igneous rocks samples were measured by Atomic Absorption Analyzer, ranged from 7.13% to 8.79%, 1.21% to 6.92%, 0.54% to 4.24%, <10 ppm, ppm to 77.06ppm, and <1 ppm to 5.58 ppm respectively.the 238 U activity concentrations of the samples are higher than those of 226 Ra and 232 Th. 40 K was found to vary with variation of rock types, it has high concentrations. The radionuclides activity concentrations values of 238 U, 226 Ra, and 40 K are the highest for the samples 1ba and 6ba. The radium equivalent activity was calculated from the concentration of the natural radionuclide where the activity range to Bq/kg with mean value Bq/kg, which is higher than the internationally accepted value 370 Bq/kg. The mean values of the annual effective dose (D eff (msv/y) was found to be less than one (0.28),This calculated value waswithin the worldwide mean values( 1for D eff (msv/y) (UNSCEAR, 2000). Gamma-ray results can be considered as a base line monitoring for natural background radioactivity levels. Acknowledgements The author is indebted to the Saudi Geological Survey (SGS) for their technical help. References 1. Ahmed N.K., Abbady A.,ElArabiAM., Michel., El-Kamel, and Abbady A.G.E,2006, Comparative study of the natural radioactivity of some selected rocks from Egypt and Germany,Indian Journal of Pure and Applied Physics, 44, Amrani, D., M. Tahtat, Natural radioactivity in Algerian building materials, Applied Radiation and Isotopes, 54: Ayodeji Awodugba1, Adetayo Abioye1, Dauda Adekunle1, Omowumi Ologun1, Isiaka Oyekunle1, Ola-tunde Oni1, Pascal Tchokossa , Basement Data of the Terrestrial Radionuclide Level of Abuja Federal. Capital Territory, (FCT), Nigeria, Journal of Environmental Protection, 2, El-Arabi A.M., 2007, 226 Ra, 232 Th and 40 K concentrations in igneous rocks from easterndesertegypt and its radiological implications, Radiation Measurements, Volume 42, Issue 1, January 2007, Pages Harb S., El-Kamel A. H., Abd El-Mageed A. I., Abbady A., andrashedw.,2008, Concentrations of 238U,235U,226Ra,232Th, and 40K for some granite samples in Eastern Desert of Egypt, Proceedings of the 3 rd Environmental Physics Conference, Aswan, Egypt. 6. Johnson P. R. and.kattan F. H, 2001, Lithostratigraphic revision in the Arabian Shield: the impacts of geochronology and tectonic analysis,the Arabian Journal for Science and Engineering, 331C, Leet L., Judson Sh., Kauffman M., (1982), Physical Geology, sixth edition, Englewood Cliffs, New Jersey Matsah M.I. and Hossain D., 1993, Ground Conditions in Al-Madinah Al-Munawarah.Saudi Arabia, JKAU: Earth Sci.. 6, Mineral Data, 2012, webmineral.com 10. Mohamed F. Raslan* and Mohamed G. El- Feky, 2012, Radioactivity and mineralogy of the altered granites of the WadiGhadir shear zone, SouthEastern Desert, Egypt, Chin. J. Geochem. 31: Saudi Geological Survey (SGS), 2012, Tufail, M., NasimAkhtar M., 2006, Measurement of terrestrial radiation for assessment of gamma dose from cultivated and barren saline soils of Faisalabad in Pakistan, Radiation Measurements, 41, UNSCEAR, 2000, United Nation Scientific Committee for the e effects of atomic radiation. 14. Veiga R, Sanches N, Anjos RM, Macario K, Bastos J, Iguatemy M, Aguiar JG, Santos AMA, Mosquera B, Carvalho C, Baptista FM, Umisedo NK, 2006, Measurement of natural radioactivity in Brazilian beach sands, Radiation Measurements. 41: /12/

Radioactivity measurements and risk assessments in soil samples at south and middle of Qatar

Radioactivity measurements and risk assessments in soil samples at south and middle of Qatar A. T. Al-Kinani*, M. A. Amr**, K. A. Al-Saad**, A. I. Helal***, and M. M. Al Dosari* *Radiation and Chemical